html - 如何在箭头周围绘制边框？

Question

我想在整个箭头周围绘制边框，但问题出在右侧，因为它在正方形周围绘制。

原因是直 Angular 三 Angular 形是透明的，它看起来是这样的。否则，如果箭头颜色相同，则看不到它们。

任何想法如何做到这一点？

这里是 jsfiddle

HTML

.firstArrow {
  position: relative;
  background: red;
  text-align: center;
  margin-right: 10px;
  margin-left: 0px;
  height: 50px;
  width: 330px;
  float: left;
  z-index: 3;
  padding-left: 50px;
  padding-top: 7px;
}

.firstArrow:before {
  content: '';
  position: absolute;
  width: 20px;
  height: 50%;
  left: 100%;
  top: 0;
  background: linear-gradient(to right top,red 50%,transparent 50%);
}

.firstArrow:after {
  content: '';
  position: absolute;
  width: 20px;
  height: 50%;
  left: 100%;
  bottom: 0;
  background: linear-gradient(to right bottom,red 50%,transparent 50%);
}

.secondArrow {
  position: relative;
  background: blue;
  margin-right: 10px;
  padding-left: 50px;
  padding-top: 7px;
  left: -20px;
  float: left;
  z-index: 2;
  height: 50px;
  width: 330px;

}
.secondArrow:before {
  content: '';
  position: absolute;
  width: 20px;
  height: 50%;
  left: 100%;   
  text-align: center;
  top: 0;
  background: linear-gradient(to right top,blue 50%,transparent 50%);
}

.secondArrow:after {
  content: '';
  position: absolute;
  width: 20px;
  height: 50%;
  left: 100%;
  bottom: 0;
  background: linear-gradient(to right bottom,blue 50%,transparent 50%);
}
.thirdArrow {
  position: relative;
  background: green;
  text-align: center;
  padding-top: 7px;
  height: 50px;
  width: 330px;
  left: -40px;
  float: left;
  z-index: 1;
}

.thirdArrow:after {
  content: '';
  position: absolute;
  width: 20px;
  height: 50%;
  left: 100%;
  bottom: 0;
  background: linear-gradient( to right bottom, green 50%,transparent 50%);
}
.thirdArrow:before {
  content: '';
  position: absolute;
  width: 20px;
  height: 50%;
  left: 100%;
  top: 0;
  background: linear-gradient( to right top, green 50%, transparent 50%);
}

<div class="firstArrow"> 1 </div>
<div class="secondArrow"> 2 </div>
<div class="thirdArrow"> 3 </div>

Answer 1

您可以使用倾斜变换以不同方式处理形状:

.arrow {
  position: relative;
  text-align: center;
  padding: 20px 0;
  width: 100px;
  float: left;
  color: #fff;
  z-index: 0;
}

.arrow:before,
.arrow:after {
  content: "";
  position: absolute;
  box-sizing: border-box;
  z-index: -1;
  top: 0;
  height: 50%;
  left: -3px;
  right: 0;
  transform: skewX(45deg);
  transform-origin: bottom;
  background: var(--c, red);
  border: 3px solid #000;
  border-bottom: 0;
}

.arrow:after {
  transform: scaleY(-1) skewX(45deg);
}

.arrow:first-child {
  overflow: hidden;
  border-left: 3px solid #000;
}

<div class="arrow"> 1 </div>
<div class="arrow" style="--c:blue;"> 2 </div>
<div class="arrow" style="--c:green;"> 3 </div>